Karl Fischer titration: difference between revisions
Diff·revision 21 → 22·18:33, 20 Oct 2024
Difference between revision 21 and revision 22 of Karl Fischer titration. 2 lines changed; the page grew by 330 bytes.
| Revision 21 — 02:27, 14 Oct 2024 Areapercent_Ayo (talk) fix category — parent was wrong 4,481 bytes ±0 | Revision 22 — 18:33, 20 Oct 2024 Retention_Time_Rae (talk) ce per MOS 4,811 bytes +330 | ||
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| 45 | For a research peptide vial nominally containing 5–10 mg of solid, only the coulometric variant is realistic: the total water present may be as little as 300 µg, which is below the practical resolution of a volumetric titration on that sample mass. Certificates reporting water content on 10 mg vials by volumetric titration should be read with that in mind.{{r|scholz1984}} | 45 | For a research peptide vial nominally containing 5–10 mg of solid, only the coulometric variant is realistic: the total water present may be as little as 300 µg, which is below the practical resolution of a volumetric titration on that sample mass. Certificates reporting water content on 10 mg vials by volumetric titration should be read with that in mind.{{r|scholz1984}} |
| 46 | 46 | ||
| + | 47 | {{note|Sample handling dominates the error budget. Lyophilised peptide is hygroscopic; a sample weighed in ambient laboratory air for two minutes can gain enough water to shift the result by a percentage point. Compendial procedure requires transfer under dry conditions, and reported values are only as good as that transfer.}} | |
| + | 48 | ||
| 47 | == References == | 49 | == References == |
| 48 | {{reflist}} | 50 | {{reflist}} |